Low-power-consumption optical fiber physiological information sensing method and device

Abstract

The invention discloses a low-power-consumption optical fiber physiological information sensing method and device. A low-power-consumption optical fiber physiological information sensing device comprises a control chip, a light source, a sensing optical fiber, a photoelectric detector, an amplifying circuit, an analog-to-digital converter and a demodulation chip. The control chip generates a pulse control signal to drive the light source, the analog-to-digital converter and the demodulation chip; the light source receives the pulse control signal and generates a pulse light signal; the sensing optical fiber is used for converting the human body weak vibration signal into the change of light intensity, namely the human body weak vibration signal is modulated to the light intensity of the pulse light signal; and the demodulation chip is used for synchronously demodulating the input signal according to the pulse control signal so as to obtain a human body weak vibration signal and extract physiological information from the human body weak vibration signal. The low-power-consumption optical fiber physiological information sensing method and the low-power-consumption optical fiber physiological information sensing device have the advantages that on the premise that the optical fiber sensing accuracy is not affected, power consumption and heating of a light source are greatly reduced, and the low-power-consumption optical fiber physiological information sensing method and the low-power-consumption optical fiber physiological information sensing device can be widely applied to portable and wearable devices.

Description

Technical Field

[0001] The present invention belongs to the field of optical fiber physiological information sensing, and in particular relates to a low-power optical fiber physiological information sensing method and device. Background Art

[0002] In recent years, optical fiber sensing is rapidly being applied and industrialized in the field of physiological information sensing. However, existing optical fiber physiological information sensing methods and devices also have some shortcomings, which limit their further development. For example, the high energy consumption of the light source makes its application in portable devices limited by the battery power; the light source is prone to heat up when it is running continuously for a long time, and there is a risk of overheating and self-ignition or overheating and damage in a closed environment such as the interlayer of a mattress or cushion. Summary of the invention

[0003] The present invention aims at the state of the prior art, overcomes the above defects, and provides a low-power optical fiber physiological information sensing method and device.

[0004] The present invention adopts the following technical scheme, a low-power optical fiber physiological information sensing device, including a control chip, a light source, a sensing optical fiber, a photodetector, an amplifier circuit, an analog-to-digital converter, and a demodulation chip, wherein:

[0005] A control chip generates a pulse control signal to drive the light source, the analog-to-digital converter and the demodulation chip;

[0006] A light source receives a pulse control signal and generates a pulse light signal;

[0007] The sensing optical fiber converts the weak vibration signal of the human body into the change of light intensity, that is, the weak vibration signal of the human body is modulated onto the light intensity of the pulse light signal;

[0008] Photodetector, which converts pulsed light signals into analog electrical signals;

[0009] Amplifier circuit, which amplifies the analog electrical signal;

[0010] Analog-to-digital converters, which convert analog electrical signals into digital signals;

[0011] The demodulation chip synchronously demodulates the input digital signal according to the pulse control signal to obtain the weak vibration signal of the human body and extract physiological information from the weak vibration signal of the human body.

[0012] As a preferred technical solution of the above technical solutions, the physiological information includes heart rate information, respiratory rate information, bed leaving information, blood pressure information, heart rate variability information, and sleep apnea information.

[0013] As a preferred technical solution of the above technical solutions, after the demodulation chip demodulates the input digital signal, it outputs a human body weak vibration signal waveform containing physiological information.

[0014] As a preferred technical solution of the above technical solutions, the demodulation chip further extracts physiological information from the waveform of the weak vibration signal of the human body through a preset method.

[0015] As a preferred technical solution of the above technical solution, after the light source starts working in the high level stage of the pulse control signal, the light intensity emitted by the light source gradually increases, which includes three stages: the rising edge of the light intensity, the oscillation period, and the steady state; assuming that the rising edge takes time t 0 , the oscillation period takes time t 1 , the sampling time of the analog-to-digital converter is t 2 , then the minimum pulse width of the pulse light signal is W = t 0 +t 1 +t 2 .

[0016] The present invention adopts the following technical scheme, a low-power optical fiber physiological information sensing method, comprising the following steps:

[0017] Step 1: The control chip generates a pulse control signal to drive the light source;

[0018] Step 2: The light source receives the pulse control signal and generates a pulse light signal;

[0019] Step 3: The sensing optical fiber converts the weak vibration signal of the human body into a change in light intensity, that is, the weak vibration signal of the human body is modulated onto the light intensity of the pulse light signal;

[0020] Step 4: The photodetector converts the pulsed light signal into an analog electrical signal;

[0021] Step 5: The amplifier circuit amplifies the analog electrical signal;

[0022] Step 6: The control chip generates a pulse control signal to drive the analog-to-digital converter;

[0023] Step 7: The analog-to-digital converter converts the analog electrical signal into a digital signal;

[0024] Step 8: The control chip generates a pulse control signal to drive the demodulation chip;

[0025] Step 9: The demodulation chip synchronously demodulates the input digital signal according to the pulse control signal to obtain the weak vibration signal of the human body and extract physiological information from the weak vibration signal of the human body.

[0026] As a preferred technical solution of the above technical solutions, the voltage loaded on the light source is driven by a pulse control signal of a control chip, and the control chip modulates the output light intensity waveform of the light source into a pulse waveform.

[0027] As a preferred technical solution of the above technical solutions, the light source outputs a pulse light signal instead of a continuous light signal.

[0028] As a preferred technical solution of the above technical solutions, the light source, analog-to-digital converter and demodulation chip are synchronously driven by the pulse control signal generated by the control chip to achieve synchronous demodulation of the pulse output optical signal.

[0029] The present invention discloses a low-power optical fiber physiological information sensing method and device, which has the beneficial effect of greatly reducing the power consumption and heat generation of the light source without affecting the accuracy of optical fiber sensing, and can be widely used in portable and wearable devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a hardware structure diagram of the present invention.

[0031] Figure 2 This is a control pulse logic timing diagram of Example 1 of the present invention.

[0032] Figure 3 It is a schematic diagram of weak vibration signals of the human body collected in Example 1 of the present invention.

[0033] Figure 4 Schematic diagram of the heart rate signal obtained in Example 1 of the present invention.

[0034] Figure 5 Schematic diagram of the respiratory rate signal obtained in Example 1 of the present invention. DETAILED DESCRIPTION

[0035] The present invention discloses a low-power optical fiber physiological information sensing method and device. Figures 1 to 5 , the specific implementation modes of the present invention are further described.

[0036] Example 1.

[0037] Preferably, if Figure 1 As shown, the low-power optical fiber physiological information sensing device includes a control chip, a light source, a sensing optical fiber, a photodetector, an amplifier circuit, an analog-to-digital converter, and a demodulation chip, wherein:

[0038] The control chip generates a pulse control signal to drive the light source, analog-to-digital converter and demodulation chip, such as Figure 2 As shown;

[0039] A light source receives a pulse control signal and generates a pulse light signal;

[0040] The sensing optical fiber converts the weak vibration signal of the human body into a change in light intensity, that is, the weak vibration signal of the human body is modulated onto the light intensity of the pulse light signal; the weak vibration signal of the human body causes the sensing optical fiber to bend to different degrees, causing the transmission loss of the sensing optical fiber to change accordingly, resulting in a corresponding change in the light intensity of the pulse light signal output by the sensing optical fiber;

[0041] Photodetector, which converts pulsed light signals into analog electrical signals;

[0042] Amplifier circuit, which amplifies the analog electrical signal;

[0043] Analog-to-digital converters, which convert analog electrical signals into digital signals;

[0044] The demodulation chip synchronously demodulates the input digital signal according to the pulse control signal to obtain the weak vibration signal of the human body and extract physiological information from the weak vibration signal of the human body.

[0045] In other words, the overall concept of this embodiment is: the pulse light signal output by the light source is modulated by the sensing optical fiber and the human body vibration signal, and then passes through the photodetector, the amplifier circuit, the analog-to-digital converter to the demodulation chip in sequence, and finally outputs the human body's heart rate, respiratory rate, getting out of bed, blood pressure, heart rate variability, sleep apnea and other physiological information.

[0046] Among them, physiological information includes heart rate information, respiratory rate information, bed leaving information, blood pressure information, heart rate variability information, and sleep apnea information.

[0047] The control chip and the demodulation chip may be the same chip or different chips.

[0048] Among them, after the demodulation chip demodulates the input digital signal, it outputs the human body weak vibration signal waveform containing physiological information, such as Figure 3 shown.

[0049] Among them, the demodulation chip further extracts physiological information such as heart rate, respiratory rate, bed leaving, blood pressure, heart rate variability, sleep apnea, etc. from the weak vibration signal waveform of the human body through a preset method. Figure 4 , Figure 5 shown.

[0050] Among them, after the light source starts working in the high-level stage of the pulse control signal, the intensity of the laser emitted by the light source gradually increases, which includes the rising edge, oscillation period, and steady state of the light intensity. The time consumption of the rising edge and oscillation period is related to the power supply voltage and temperature. Assume that the rising edge time t 0 , the oscillation period takes time t 1 , the sampling time of the analog-to-digital converter is t 2 , then the minimum pulse width of the pulse light signal is W = t 0 +t1 +t 2 .

[0051] The smaller the duty cycle of the pulse light signal, the lower the power consumption of the light source. Let DR be the duty cycle, then DR = w × f, where w is the light source pulse width, and f is the sampling frequency. In this embodiment, assuming that the sampling frequency is 250 Hz, the period of the pulse light signal is 4 milliseconds, and the light source pulse width is 100 microseconds, the duty cycle of the pulse light signal is 2.5%, which can theoretically reduce the power consumption of the light source by about 97.5%.

[0052] Preferably, a low-power optical fiber physiological information sensing method comprises the following steps:

[0053] Step 1: The control chip generates a pulse control signal to drive the light source;

[0054] Step 2: The light source receives the pulse control signal and generates a pulse light signal;

[0055] Step 3: The sensing optical fiber converts the weak vibration signal of the human body into a change in light intensity, that is, the weak vibration signal of the human body is modulated onto the light intensity of the pulse light signal; the weak vibration signal of the human body causes the sensing optical fiber to bend to varying degrees, causing the transmission loss of the sensing optical fiber to change accordingly, resulting in a corresponding change in the light intensity of the pulse light signal output by the sensing optical fiber;

[0056] Step 4: The photodetector converts the pulsed light signal into an analog electrical signal;

[0057] Step 5: The amplifier circuit amplifies the analog electrical signal;

[0058] Step 6: The control chip generates a pulse control signal to drive the analog-to-digital converter;

[0059] Step 7: The analog-to-digital converter converts the analog electrical signal into a digital signal;

[0060] Step 8: The control chip generates a pulse control signal to drive the demodulation chip;

[0061] Step 9: The demodulation chip synchronously demodulates the input digital signal according to the pulse control signal to obtain the weak vibration signal of the human body and extract physiological information from the weak vibration signal of the human body.

[0062] The voltage loaded on the light source is driven by a pulse control signal of a control chip, and the control chip modulates the output light intensity waveform of the light source into a pulse waveform.

[0063] Wherein, the light source outputs a pulse light signal instead of a continuous light signal.

[0064] Among them, the pulse control signal generated by the control chip synchronously drives the light source, analog-to-digital converter and demodulation chip to achieve synchronous demodulation of the pulse output light signal. The driving time of the three can be consistent or slightly delayed.

[0065] It is worth mentioning that the technical features such as the specific models of the control chip and demodulation chip involved in the patent application of the present invention should be regarded as the prior art. The specific structure, working principle and possible control method and spatial layout method of these technical features can be selected according to the conventional selection in the field, and should not be regarded as the inventive point of the patent of the present invention. The patent of the present invention will not be further elaborated.

[0066] For those skilled in the art, it is still possible to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A low-power optical fiber physiological information sensing device, characterized in that: It includes a control chip, a light source, a sensing optical fiber, a photodetector, an amplifier circuit, an analog-to-digital converter, and a demodulation chip, among which: A control chip generates a pulse control signal to drive the light source, the analog-to-digital converter and the demodulation chip; A light source receives a pulse control signal and generates a pulse light signal; The sensing optical fiber converts the weak vibration signal of the human body into the change of light intensity, that is, the weak vibration signal of the human body is modulated onto the light intensity of the pulse light signal; Photodetector, which converts pulsed light signals into analog electrical signals; Amplifier circuit, which amplifies the analog electrical signal; Analog-to-digital converters, which convert analog electrical signals into digital signals; The demodulation chip synchronously demodulates the input digital signal according to the pulse control signal to obtain the weak vibration signal of the human body and extract physiological information from the weak vibration signal of the human body.

2. A low-power optical fiber physiological information sensing device according to claim 1, characterized in that: Physiological information includes heart rate information, respiratory rate information, bed leaving information, blood pressure information, heart rate variability information, and sleep apnea information.

3. A low-power optical fiber physiological information sensing device according to claim 1, characterized in that: After the demodulation chip demodulates the input digital signal, it outputs a waveform of a weak human body vibration signal containing physiological information.

4. A low-power optical fiber physiological information sensing device according to claim 3, characterized in that: The demodulation chip further extracts physiological information from the weak vibration signal waveform of the human body through a preset method.

5. A low-power optical fiber physiological information sensing device according to claim 1, characterized in that: After the light source starts working in the high-level stage of the pulse control signal, the intensity of the laser emitted by the light source gradually increases, which includes three stages: the rising edge, oscillation period, and steady state of the light intensity; assuming that the rising edge takes t0, the oscillation period takes t1, and the analog-to-digital converter sampling takes t2, the minimum pulse width of the pulse light signal is W=t0+t1+t2.

6. A low-power optical fiber physiological information sensing method, characterized in that: The following steps are involved: Step 1: The control chip generates a pulse control signal to drive the light source; Step 2: The light source receives the pulse control signal and generates a pulse light signal; Step 3: The sensing optical fiber converts the weak vibration signal of the human body into a change in light intensity, that is, the weak vibration signal of the human body is modulated onto the light intensity of the pulse light signal; Step 4: The photodetector converts the pulsed light signal into an analog electrical signal; Step 5: The amplifier circuit amplifies the analog electrical signal; Step 6: The control chip generates a pulse control signal to drive the analog-to-digital converter; Step 7: The analog-to-digital converter converts the analog electrical signal into a digital signal; Step 8: The control chip generates a pulse control signal to drive the demodulation chip; Step 9: The demodulation chip synchronously demodulates the input digital signal according to the pulse control signal to obtain the weak vibration signal of the human body and extract physiological information from the weak vibration signal of the human body.

7. A low-power optical fiber physiological information sensing method according to claim 6, characterized in that: The voltage loaded on the light source is driven by the pulse control signal of the control chip, and the control chip modulates the output light intensity waveform of the light source into a pulse waveform.

8. A low-power optical fiber physiological information sensing method according to claim 6, characterized in that: The light source outputs a pulsed light signal instead of a continuous light signal.

9. A low-power optical fiber physiological information sensing method according to claim 6, characterized in that: The pulse control signal generated by the control chip is used to synchronously drive the light source, analog-to-digital converter and demodulation chip to achieve synchronous demodulation of the pulse output optical signal.

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